Isolators are usually used for isolating crankshaft pulley from torsion vibration at the crankshaft that is a result of vibration in torque that occurs in internal combustion engines and in particular those with certain cylinder counts such as four-or-three cylinder engines, and diesel engines, and they are also used in extreme conditions, such as during the engine startup and accelerations or decelerations of the engine crankshaft relative to the pulley. In addition isolators can operate in an “engine-driven” mode with the engine crankshaft is driven by the belt.